EP 2 365 866 discloses a system for treatment of flue gas for removing NOx and SO2 comprising a compressor and a wet scrubber wherein the flue gas is transported counter currently to a wash medium. In addition, between the compressor and the wet scrubber, a basic additive is supplied to limit the acidity of the water coming from the wet scrubber and thus protect the plant.
WO 2011/140 054 discloses a system for treatment of flue gas including a condenser to remove water from the flue gas, a compressor and a wet scrubber column for NOx removal. In addition, the water gathered at the condenser (this is waste water) is supplied from the condenser to the wet scrubber. According to WO 2011/140 054, after having passed through the wet scrubber, the water is collected as acid water and is disposed.
This system requires a large amount of water and, in addition generates a large amount of acid water at the wet scrubber. The present invention proposes a way to overcome these drawbacks.